JP2004129066A - Multiband radio - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a multiband radio capable of suppressing a sharp increase in cost of circuit component or power consumption by having a plurality of wide-band transmission/reception section of the same configuration. <P>SOLUTION: A multiband radio is provided with: a first transmission/reception section for operating in the prescribed frequency range; a second transmission/reception section which operable frequency range is the same with the whole of one part of the operable frequency of the first transmission/reception section, in a plurality of transmission/reception sections; a switching part for switching the connection in the first transmission/reception section and the second transmission/reception section; and a control part for switching the switching part based on the reception signal and controlling the transmission/reception by sharing the frequency converting part converting IF frequency and RF frequency of the first and the second transmission/reception sections when the first and second transmission/reception sections transmit/receive in the operable frequency range. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a multi-band wireless device in which a plurality of transmitting / receiving units operate simultaneously to process independent wireless channels that handle a plurality of signals.
[0002]
[Prior art]
For radio equipment that supports multiple radio systems and multiple frequency bands, such as software defined radios, there are methods such as inter-system diversity, inter-system soft over, or using multiple radio systems simultaneously to improve communication speed. Commonly used.
In SDMA (space division multiple access), in order to increase the communication capacity (the number of accommodated stations), space-time division is performed using a smart antenna that can change the directivity of the antenna according to the propagation environment. Thereby realizing multiple access without increasing the bandwidth.
These systems have a plurality of broadband transceivers for processing independent radio channels that handle a plurality of signals, and the plurality of transceivers operate simultaneously.
In a conventional multi-band wireless device, an RF unit covering a wide band for all channels is provided in each of the plurality of transmitting and receiving units so that simultaneous operation of each channel flexibly corresponds to a wireless system.
[0003]
[Problems to be solved by the invention]
However, in a configuration having a plurality of identical wide-band transmission / reception units, there is a problem that the increase in the circuit scale causes a significant increase in cost, size, and power consumption.
[0004]
The present invention has been made in view of such circumstances, and an object of the present invention is to provide a multi-band radio that suppresses a significant increase in circuit component cost and power consumption due to having a plurality of broadband transmission / reception units having the same configuration. The machine.
[0005]
[Means for Solving the Problems]
The present invention has been made to solve the above problems, and the invention according to claim 1 is a multi-band wireless device having a plurality of transmitting and receiving units that simultaneously receive or transmit at a plurality of frequencies, or transmit and receive, Among the plurality of transmitting / receiving units, a first transmitting / receiving unit operating in a predetermined frequency range and an operable frequency range are identical to all or a part of the operable frequency range of the first transmitting / receiving unit. A second transmission / reception unit, a switch unit for switching connections in the first transmission / reception unit and the second transmission / reception unit, and a frequency range in which both the first transmission / reception unit and the second transmission / reception unit can operate. When performing transmission and reception, a frequency converter that converts the IF frequency and the RF frequency of the first transceiver and the second transceiver by switching the switch based on a received signal. Characterized by a control unit for controlling the transmission and reception shared.
[0006]
According to a second aspect of the present invention, in the first aspect of the present invention, when the first transmitting / receiving section and the second transmitting / receiving section operate at the same channel frequency, the control section performs the first control. The transmission / reception is controlled by sharing the local oscillator of the transmission / reception unit and the local oscillator of the second transmission / reception unit.
[0007]
According to a third aspect of the present invention, in the first aspect of the present invention, the frequency conversion unit shared on the receiving side includes frequency conversion means for converting a plurality of RF frequency channel signals into a predetermined IF frequency. It is characterized by doing.
[0008]
According to a fourth aspect of the present invention, in the third aspect of the present invention, among the frequency converters provided in the first transmitting / receiving section or the second transmitting / receiving section, an unshared frequency converting section stops operating. It is characterized by doing.
[0009]
According to a fifth aspect of the present invention, in the first aspect of the present invention, the frequency conversion unit shared on the transmission side transmits the modulated IF signal or baseband signal to the first transmission / reception unit and the second transmission / reception unit. A signal adding means for combining a plurality of IF signals frequency-converted to an IF frequency having an offset of a channel frequency from the IF center frequency of the unit; and a frequency converting means for converting the combined IF signal to a predetermined RF frequency. It is characterized by the following.
[0010]
According to a sixth aspect of the present invention, in the invention of the fifth aspect, among the frequency converters provided in the first transmitting / receiving section or the second transmitting / receiving section, an unshared frequency converting section stops operating. It is characterized by doing.
[0011]
According to a seventh aspect of the present invention, in the third or fifth aspect of the present invention, the frequency conversion means converts the bandwidth of the IF filter to a bandwidth including a plurality of channel signals of RF frequencies for frequency conversion. Switching is characterized.
[0012]
According to an eighth aspect of the present invention, in the first aspect, the control unit shares a frequency conversion unit that converts the IF frequency and the RF frequency in accordance with the transmission power of each of the shared transmission and reception units. The number of transmission / reception units to be controlled is controlled.
[0013]
BEST MODE FOR CARRYING OUT THE INVENTION
First, the basic concept of the present invention will be described. The present invention optimizes RF hardware resources in order to suppress an increase in circuit scale due to having a plurality of wide area transmission / reception units. That is, in a wireless device that simultaneously communicates at two or more different frequencies (frequency bands or channels), the frequency coverage of the transmitting / receiving unit that is independent for each frequency is set to a predetermined range. Further, when a plurality of transmitting / receiving sections operate in the same frequency band, a part of the transmitting / receiving sections is shared. Further, when a plurality of transmitting / receiving sections operate in the same frequency band, the local oscillator before the RF section is shared with the local oscillator.
[0014]
Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing the overall configuration of the multi-band wireless device of the present embodiment. The multi-band wireless device according to the present embodiment includes five channels of transmission / reception units A to E, antennas 42A to 42E, switches 22, switches 41B to 41E, modems 21A to 21E, a control unit 100, and an upper layer processing unit 200.
2 to 6 show circuit configuration diagrams of the transmission / reception units A to E. The transmission / reception units A and B can operate in the 800 MHz band to the 2.4 GHz band as shown in FIGS. 2 and 3, and the transmission / reception units C and D operate in the 2.4 GHz band as shown in FIGS. As shown in FIG. 6, the 5 GHz band and the transmission / reception unit E can operate in the 800 MHz band to the 5 GHz band.
[0015]
The multi-band wireless device of the present embodiment uses a cellular system when used outdoors, and uses a wireless LAN indoors or in a limited area where a wireless LAN or the like is serviced. In order to realize smooth handover without communication interruption, it is necessary to perform inter-system soft handover by simultaneously operating two transmission / reception units for cellular and wireless LAN having different frequency bands. When handover is performed between a plurality of systems having different channels in one frequency band, even if a plurality of transmission / reception units are provided, if there is no overlap in their respective coverage ranges, different radio systems in a target frequency band are used. Soft handover cannot be performed between For this reason, in the present embodiment, a transmitting / receiving unit E operable in at least one of all frequency bands (800 MHz band to 5 GHz band) is provided first.
[0016]
However, since it is not easy to realize an RF unit that can operate in all areas from a low frequency band to a high frequency band, a transmitting / receiving unit that operates in the lower frequency band of the required frequency band and an RF unit that operates in the high frequency band are required. And a transmission / reception unit that can easily design other transmission / reception units. That is, the above-mentioned frequency band is further divided into, for example, two frequency bands (800 MHz band to 2.4 GHz band and 2.4 GHz band to 5 GHz band), and the transmission / reception units A and B that can operate only in each frequency band. Transceiver units C and D are provided, and simultaneous operation at the target frequency is realized by a total of five transceiver units.
[0017]
Furthermore, not only in the RF section, but also in the IF section and the modulation / demodulation section, the channel bandwidth is low at low frequencies and the communication speed is slow enough to be suitable mainly for voice, whereas the channel bandwidth is high at high frequencies. The communication speed is wide and the speed is very high for transmitting images and large-capacity files. Since the communication speed and the channel band are different in this way, efficient design of the modem unit from the RF unit is facilitated by dividing the operation range of each transmission / reception unit.
[0018]
As shown in FIG. 2 to FIG. 6, the circuit configuration of the transmission / reception units A to E mainly includes an RF unit, an IF unit, and a baseband unit, and the configurations of switches and adders are different. Hereinafter, first, the circuit configuration of the transmission / reception unit A will be described with reference to FIG.
The transmitting / receiving unit A includes an RF amplifier 1A, mixers 2A, 7A, 11A, 16A, local oscillators 3A, 9A, IF filters 4A, 15A, IF amplifiers 5A, 14A, an AD converter 6A, and a BB (= baseband) filter 8A, 10A. , An adder 12A, a DA converter 13A, and a power amplifier 17A. The receiving side converts the RF signal input from the antenna 42A into a BB signal and outputs the BB signal to the modem 21, and the transmitting side receives the input from the modem 21. The BB signal is converted into an RF signal and output to the antenna 42A.
[0019]
Similarly, the other transmission / reception units B to E have the above-described configuration. The transmission / reception unit B is provided with a new switch 30B / 31B / 32B and an adder 33B in the transmission / reception unit A, and an adder corresponding to the adder 12A. It is a configuration that does not have any.
The transmission / reception unit C has a configuration in which switches 30C, 31C, 32C, and 34C and an adder 33C are newly provided in the transmission / reception unit A.
The transmission / reception unit D has a configuration in which switches 30D, 31D, and 32D and an adder 33D are newly provided in the transmission / reception unit A, and an adder corresponding to the adder 12A is not provided.
The transmission / reception unit E has a configuration in which switches 30E, 31E, and 32E are newly provided in the transmission / reception unit A, and does not include an adder corresponding to the adder 12A.
[0020]
The feature of the transceiver A in the present embodiment is that, on the reception side, the output signal of the AD converter 6A is transmitted to the switch 31B of the transceiver B via the line A3, to the switch 31C of the transceiver C via B3, and to the switch C5. Is output to the switch 31D of the transmitter / receiver D via the D and to the switch 31E of the transmitter / receiver E via the D5. On the transmission side, the adder 12A adds the output of the mixer 11A and the output (line A4) of the adder 33B of the transceiver B, and the adder 33B outputs the output of the mixer 11B and the adder of the transceiver C. The output of the mixer 33C is added to the output of the mixer 11D, and the adder 33C adds the output of the mixer 11C and the output of the adder 33D of the transceiver D (line C7). The difference is that the output (line D7) of the mixer 11E of the transceiver D is added.
[0021]
The characteristics of the transceiver A described above are the same in the transceiver C. On the reception side, the output signal of the AD converter 6C in the transceiver C is also output to the switches 31D and 31E of the transceivers D and E. .
On the transmitting side, the output signals of the mixers 11D and 11E of the transceivers DE and E are input and combined by the adder 12C.
[0022]
The control unit 100 controls the opening and closing of the switch based on the signal information output from each of the transmission / reception units A to E. That is, the control unit 100 controls the input signals from the antennas 42A to 42E to be input to the transmission / reception units A to E by switching the switches 41B to 41E, and the output output from the transmission / reception units A to E by the switch 22. Control is performed to output a signal to each of the modems 21A to 21E. In addition to controlling to output the signals output by the modems 21A to 21E to the transmission / reception units A to E, the switches 41B to 41E are switched to output the signals output by the transmission / reception units A to E to the antennas 42A to 42E. Control.
[0023]
Hereinafter, a specific operation of the multi-band wireless device according to the present embodiment will be described. When the transmitter / receiver is shared, which transmitter / receiver operates at the same time will be classified and described for each of the following four cases.
(Case 1)
When voice communication using a cellular system based on 800-MHz band CDMA and software download using a 5-GHz high-speed wireless LAN are performed simultaneously, the transceiver A and the transceiver C are operated simultaneously. In this case, the control unit 100 controls the switch 41C to connect the antenna 42C and the transmission / reception unit C. At this time, since the frequency bands handled by the transceiver A and the transceiver C are different from each other, the circuits are not shared.
When performing reception diversity in the cellular system, the control unit 100 further operates the reception units of the transmission / reception unit B simultaneously.
[0024]
(Case 2)
When performing an inter-system handover to a system in which communication cost or communication quality is advantageous, either a 800 MHz band TDMA cellular system to an 800 MHz band CDMA cellular system or a 2 GHz band CDMA cellular system, the 800 MHz band TDMA is used. Uses the transmitting / receiving unit A, uses the transmitting / receiving unit B for CDMA in the 800 MHz band, and uses the transmitting / receiving unit E for CDMA in the 2 GHz band. That is, after the handover is completed, the voice processing is taken over from the transmitting / receiving unit A to the transmitting / receiving unit B or the transmitting / receiving unit E. Hereinafter, circuit sharing when A and B operate simultaneously will be described.
[0025]
On the receiving side, the transmission / reception unit A operates as a wide down converter that frequency-converts TDMA and CDMA RF signals into IF signals. That is, the TDMA and CDMA RF signals input from the antenna 42A are amplified by the RF amplifier 1A and converted into TDMA and CDMA IF signals by the local oscillator 3A and the mixer 2A. This IF signal is filtered by the IF filter 5A and then amplified again by the IF amplifier. Then, after being digitally converted by the AD converter 6A, it is input to the mixer 7B of the transmission / reception unit B via the mixer 7A and the line A3 and the switch 31. The mixer 7A operates as a down converter that converts a TDMAIF signal into a TDMABB signal, and the mixer 7B operates as a down converter that converts a CDMAIF signal into a CDMABB signal. The output TDMABB signal is filtered by the BB filter 8A and then output to the modem 21A via the switch 22. Further, the CDMABB signal is filtered by the BB filter 8B and then output to the modem 21B via the switch 22. The signals input to the modems 21A and 21B are demodulated and input to the upper layer processing unit 200.
[0026]
On the transmitting side, the transmitting / receiving unit A operates as a wide-up converter for frequency-converting TDMA and CDMA IF signals into RF signals. That is, the TDMABB signal input to the BB filter 10A of the transceiver A is filtered and then frequency-converted into a TDMAIF signal in the mixer 11A of the transceiver A. Further, the CDMABB signal input to the BB filter 10B of the transceiver B is filtered and then frequency-converted into a CDMAIF signal in the mixer 11B of the transceiver B. The TDMAIF signal and the CDMAIF signal are output to the adder 12A via the A4, the switch 32B, and the adder 33B, and are combined. The combined TDMA and CDMA IF signals are converted into analog signals by the DA converter 13A and then amplified by the IF amplifier. The amplified TDMA and CDMA IF signals are filtered by an IF filter 15A, and then frequency-converted into TDMA and CDMA RF signals by a local oscillator 3A and a mixer 16A. After the TDMA and CDMA RF signals are amplified by the power amplifier 17A, they are output to the antenna 42A and transmitted.
[0027]
At this time, the operation of the RF amplifier 1B to the AD converter 6B and the DA converter 13B to the power amplifier 17B, which are the RF front end units of the transmitting and receiving unit B which are not used, is stopped.
When the total transmission power of the transmission / reception units A and B exceeds the allowable power of the power amplifier 17A of the transmission / reception unit A, the transmission / reception units A and B do not share a circuit in transmission, and the power of each circuit is not shared. Amplifiers 17A and 17B are used.
[0028]
As described in detail above, sharing the circuits of the transmission / reception unit A and the transmission / reception unit B can reduce an increase in power consumption.
[0029]
(Case 3)
In Case 2, a case will be described in which the CDMA transmitting / receiving section B in the 800 MHz band is also required as a handover destination and the transmitting / receiving sections A, B, and E share a circuit. Similarly to the operation of the transmission / reception unit B in Case 2, the transmission / reception unit E operates as a down converter that converts a CDMAIF signal into a CDMABB signal during reception. That is, the IF signal digitally converted by the AD converter 6A of the transmission / reception unit A is received by the mixer 7E and frequency-converted to a CDMABB signal. The CDMABB signal is input to the modem 21E via the switch 22, demodulated, and output to the upper layer processing unit 200.
Further, at the time of transmission, the transmission / reception unit E filters the CDMABB signal by the BB filter 10E, and then frequency-converts the CDMABB signal into a CDMAIF signal by the mixer 11E. The CDMA IF signal frequency-converted by the transmission / reception unit E is output from the switch 32E to the adder 12A, and is combined with the TDMA IF signal frequency-converted by the transmission / reception unit A and the CDMA IF signal frequency-converted by the transmission / reception unit B.
[0030]
At this time, the operation of the RF amplifier 1E to the AD converter 6E and the DA converter 13E to the power amplifier 17E, which are the RF front end units of the transmitting and receiving unit E which are not used, is stopped.
When the total transmission power of the transmission / reception units A, B, and E exceeds the allowable power of the power amplifier 17A of the transmission / reception unit A, the transmission / reception units A, B, and E share a circuit in transmission. Instead, the power amplifiers 17A, 17B and 17E of the respective circuits are used.
[0031]
As described in detail above, even when the operable range of the transmission / reception unit A or the transmission / reception unit B is set to be narrower than that of the transmission / reception unit E, sufficient flexibility regarding circuit sharing can be secured, and a redundant circuit can be secured. And cost can be reduced.
[0032]
(Case 4)
When using a 2.4 GHz band wireless LAN to increase the speed to 55 Mbps of 11 Mbps by using a MIMO (Multi Input Multi Output) system of five channels for transmission and reception, the transmission and reception units A to E are simultaneously operated and the switches 41B to 41E are operated. By controlling, the antennas 42A to 42E are individually connected. At this time, by controlling the switches 30B to 30E, the output signal of the local oscillator 3A is sent to the mixers 2B to 2E and 16B to 16E to share the local signal. At this time, by stopping the local oscillators 3B to 3E, the power consumption of the local oscillators 3A to 3E can be reduced to 1/5.
[0033]
Note that, in the present embodiment, an example of a wireless configuration that performs digitization at the IF is shown, and signal separation from the shared receiving unit and signal addition to the shared transmitting unit are performed by the digital unit. Thereby, many analog circuits can be shared. At the same time, by dividing the dynamic range necessary for the analog section into a plurality of parts, a high-performance component is not required for separating the received signal and adding the transmitted signal in the analog section, so that the cost can be greatly reduced.
[0034]
【The invention's effect】
As described above, according to the first aspect of the present invention, the first transmitting / receiving section operating in a predetermined frequency range among the plurality of transmitting / receiving sections, and the operable frequency range is set to the operable frequency range of the first transmitting / receiving section. A second transmission / reception unit identical to the whole or a part of the first transmission / reception unit, a switch unit for switching connection between the first transmission / reception unit and the second transmission / reception unit, and both the first transmission / reception unit and the second transmission / reception unit operate When transmission and reception are performed in a possible frequency range, the switch unit is switched based on the received signal, and the frequency conversion unit that converts the IF frequency and the RF frequency of the first transmission and reception unit and the second transmission and reception unit is shared. And a control unit for controlling the power consumption of the wideband transmission / reception unit having the same configuration.
[0035]
According to a second aspect of the present invention, in the first aspect of the present invention, when the first transceiver and the second transceiver operate at the same channel frequency, the controller transmits the first transceiver and the second transceiver. Since transmission / reception is controlled by sharing the local oscillator of the two transmission / reception units, the effect of reducing power consumption related to the local oscillator can be obtained.
[Brief description of the drawings]
FIG. 1 is a block diagram illustrating an overall configuration of a multi-band wireless device according to an embodiment.
FIG. 2 is a circuit configuration diagram of a transmission / reception unit A in FIG.
FIG. 3 is a circuit configuration diagram of a transmission / reception unit B in FIG. 1;
FIG. 4 is a circuit configuration diagram of a transmission / reception unit C in FIG. 1;
FIG. 5 is a circuit configuration diagram of a transmission / reception unit D in FIG. 1;
FIG. 6 is a circuit configuration diagram of a transmission / reception unit E in FIG. 1;
[Explanation of symbols]
A to E transmission / reception units 21A to 21E modems 22, 41B to 41E switches 42A to 42E antennas 100 control unit 200 upper layer processing unit

Claims (8)

In a multi-band radio having a plurality of transmission / reception units that simultaneously receive or transmit at a plurality of frequencies, or transmit and receive,
A first transmitting / receiving unit operating in a predetermined frequency range among the plurality of transmitting / receiving units;
An operable frequency range is the same as the whole or a part of the operable frequency range of the first transmitting / receiving unit, and a second transmitting / receiving unit;
A switch unit that switches a connection in the first transmission / reception unit and the second transmission / reception unit;
When transmitting and receiving in a frequency range in which both the first transmitting and receiving unit and the second transmitting and receiving unit can operate, the switch unit is switched based on a received signal, and the first transmitting and receiving unit and the second transmitting and receiving unit are switched. A multi-band wireless device comprising: a control unit that controls transmission and reception by sharing a frequency conversion unit that converts an IF frequency and an RF frequency of the unit. When the first transceiver and the second transceiver operate at the same channel frequency, the controller performs transmission and reception by sharing a local oscillator of the first transceiver and the second transceiver. 2. The multi-band wireless device according to claim 1, wherein the operation is controlled. 2. The multi-band wireless device according to claim 1, wherein the frequency conversion unit shared on the receiving side includes frequency conversion means for frequency-converting a plurality of RF frequency channel signals into a predetermined IF frequency. 4. The multi-band wireless device according to claim 3, wherein, among the frequency converters included in the first transmitting / receiving unit or the second transmitting / receiving unit, an unshared frequency converter stops operating. 5. The frequency conversion unit shared on the transmission side frequency-converts the modulated IF signal or baseband signal into an IF frequency having a channel frequency offset from the IF center frequency of the first transmission / reception unit and the second transmission / reception unit. 2. The multi-band wireless device according to claim 1, further comprising: signal addition means for combining a plurality of IF signals; and frequency conversion means for converting the combined IF signals into a predetermined RF frequency. The multi-band wireless device according to claim 5, wherein, among the frequency converters included in the first transceiver unit or the second transceiver unit, an unshared frequency converter stops operating. 6. The multi-band wireless device according to claim 3, wherein the frequency conversion unit switches a bandwidth of the IF filter to a bandwidth including a plurality of channel signals of an RF frequency for frequency conversion. The control unit controls the number of a plurality of transmitting / receiving units sharing a frequency conversion unit that performs conversion between the IF frequency and the RF frequency according to transmission power of each shared transmitting / receiving unit. A multi-band radio according to claim 1.

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